Physical Review Letters
Green's Functions in the Theory of Many-Fermion Systems
Mark Bolsterli
Abstract
It is shown that the usual single-particle Green's function does not give direct information about the lowest excitation energies if there is a pairing energy (of the type familiar in nuclear physics). An alternate Green's function is suggested which will provide such information. (C.J.G.) It is noted that owing to the similarity existing between electromagnetic interaction and the vector part of the weak interaction proposed by Feynman and Gell-Mann, the contribution of the vector part of the weak interaction to mu /sup -/ capture by a proton is closely related to the electromagnetic form factors of the nucleon. Formula for the capture probability calculated with the renormaalized V-A, weak interaction is given. The correction to the contribution of the vector part of the weak interaction due to the charge and magnetic moment distribution of the nucleon is estimated on the basis of the data from electron-nucleon scattering experiments. (auth)